1. Field of the Invention
This invention relates to vehicles, and in particular, an omnidirectional wheelchair base in which the frame provides integral chassis suspension and support for the wheelchair.
2. Description of the Prior Art
Many types of omnidirectional vehicles are known in the art. For example, La in U.S. Pat. No. 4,237,990 describes an omnidirectional bumper car for amusement parks. Ziegler in U.S. Pat. No. 3,295,700 describes an omnidirectional vehicle for use in handling radioactive materials. Suitable wheels for such vehicles are described in U.S. Pat. No. 3,789,947 to Blumrich and U.S. Pat. No. 3,876,255 to Ilon.
These patents typify the prior approaches to omnidirectional vehicles in which size and weight were not significant factors in the design of the vehicle. The ride qualities of these prior art vehicles were determined mainly by the resiliency of the tires or wheels employed. The omnidirectional nature of the vehicle made provision of other suspension systems difficult. In addition, the cumbersome design of these prior art omnidirectional vehicles rendered them inapplicable to wheelchairs, in which all of the propulsion, suspension, and control must be situated in a relatively small area beneath the seat of a chair.